Locally optimal controllers and globally inverse optimal controllers

In this paper we consider the problem of global asymptotic stabilization with prescribed local behavior. We show that this problem can be formulated in terms of control Lyapunov functions. Moreover, we show that if the local control law has been synthesized employing an LQ approach, then the associated Lyapunov function can be seen as the value function of an optimal problem with some specific local properties. We illustrate these results on two specific classes of systems: backstepping and feedforward systems. Finally, we show how this framework can be employed when considering the orbital transfer problem.     

Saturation-based switching anti-windup design for linear systems with nested input saturation

This paper proposes a saturation-based switching anti-windup design for the enlargement of the domain of attraction of a linear system subject to nested saturation. A nestedly saturated linear feedback is expressed as a linear combination of a set of auxiliary linear feedbacks, which form a convex hull where the nestedly saturated linear feedback resides. This set of auxiliary linear feedbacks is then partitioned into several subsets. The auxiliary linear feedbacks in each of these subsets form a convex sub-hull of the original convex hull. When the value of the nestedly saturated linear feedback falls into a convex sub-hull, it can be expressed as a linear combination of the subset of all the auxiliary feedbacks that form the convex sub-hull. A separate anti-windup gain is designed for each convex sub-hull by using a common quadratic Lyapunov function and is implemented when the value of the nestedly saturated linear feedback falls into this convex sub-hull. Simulation results indicate that such a saturation-based switching anti-windup design has the ability to significantly enlarge the domain of attraction of the closed-loop system.     

Quadratic control of stochastic hybrid systems with renewal transitions

We study the quadratic control of a class of stochastic hybrid systems with linear continuous dynamics for which the lengths of time that the system stays in each mode are independent random variables with given probability distribution functions. We derive a condition for finding the optimal feedback policy that minimizes a discounted infinite horizon cost. We show that the optimal cost is the solution to a set of differential equations with unknown boundary conditions. Furthermore, we provide a recursive algorithm for computing the optimal cost and the optimal feedback policy. The applicability of our result is illustrated through a numerical example, motivated by stochastic gene regulation in biology.     

压力容器用封头制造质量控制和专业化生产发展方向

中国法规首次对压力容器等特种设备用封头实施制造资格许可和强制的监督检验制度。本文根据法规标准的规定,对压力容器封头制造质量控制和专业化生产发展方向的要求作一系统的综述,以提高压力容器产品的整体质量,确保特种设备安全万无一失。     

集散控制装置的实验功能开发

以一个模拟生产设备为监控对象,介绍了PCS型集散控制装置的硬件和软件组成,并开发了该装置的各种实验功能,可满足实验教学的要求。     

苗家坝-碧口梯级水库汛期水位动态控制研究

本文将单一水库预泄能力约束法,推广到梯级水库汛期水位动态控制中,并建立了梯级水库汛期水位联合运用和动态控制模型,假定预报信息准确,在不降低下游保护对象的防洪标准的前提下,最大限度发挥梯级水库的兴利效益。以苗家坝、碧口水库为对象进行了实时调度模拟,其结果相比于原设计汛限水位动态控制方案,减少了弃水,且保证最大出库流量均在可控范围内,达到在不降低防洪标准的前提下提高梯级水库兴利效益的目的,大大提高了洪水资源利用率。     

渠首水位实时调控模型——以船行灌区一支渠为例

很多大中型灌区在输配水过程中存在水位衔接不当的问题,加之田面高程存在起伏,使得灌溉时往往存在部分田面不能上水或受淹等问题。本文提出了空间灌溉率的概念,并利用GIS的三维分析功能研究了其与渠道渠首水位之间的关系。分析表明,空间灌溉率与渠首水位之间的关系符合Logistic曲线;针对船行灌区一支渠,得到该Logistic曲线的参数,并确定了一支渠渠首和干渠渠首不同空间灌溉率所需的水位,为灌区水位实时调控提供基础数据。     

控制图在复极电解槽控制中的应用

根据离子膜制碱工艺的特点，与控制图的应用理论相结合，寻找控制对象并选择控制图的类型。通过选择合适的工艺参数，使用控制图的数据处理技术对实际数据进行处理，绘制出控制图，利用参数波动符合正态分布的特点对控制图的波动情况进行分析，用来诊断电解槽运行的受控情况。     

航空胶片显影液调整的计算机处理方法

为解决航空胶片显影液调整问题，采用了Visual Basic6.0开发了“显影液化学分析调整软件，该系统具有一定的应用价值。     

GRM-2SD120棉线缠绕机

介绍了GRM－2SD120棉线缠绕机的结构原理，重点介绍了该机的锭子部分，口型部分，锭子盘，中胶部分，传动原理，电气原理及主要技术参数。